Scientists already knew that cane toads communicate with pheromones and use these chemical signals to locate tasty eggs. They also wondered if the pheromones have another, more insidious, purpose. Biologists at the University of Sydney set up a simple experiment to find out. They placed cane toad eggs in 20 containers filled partially with water; in 10 of those containers, they added tadpoles and separated them from the eggs with mesh screens.

The researchers believe that older tadpoles released pheromones into the water, as evidenced by the water’s increased ammonia content, though they don’t yet know if the chemical release is continuous or sparked by the presence of nearby eggs. They also don’t know if this murderous adaptation evolved in response to food competition—if the pheromones are “designed” to do that—or if it’s a fortuitous coincidental effect.

Either way, try not to feel too bad for the little buggers. Introduced to Queensland in 1935 to control cane beetles, the poisonous amphibians have since spread rapidly across parts of Australia, wreaking havoc on the populations of other animal species. Oh, and they’ve failed miserably with their original job.

With all this in mind, the researchers believe that identifying the destructive pheromone will lead to a chemical control for the toad menace. Will it work? Absolutely not, thinks frog expert Mike Tyler—the cane toad now covers too much ground for a chemical solution. “It’s physically and utterly impossible,” he told Cosmos Magazine. Ouch.